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71.
72.
The monosaccharide and polyalcohol composition of 28-samples of different commercial tannins, including oak wood, grape seed and skin, plant gall, chestnut, quebracho and gambier, has been evaluated by gas chromatography–mass spectrometry after derivatization into their trimethylsilyl ethers. Quercitol was found to be characteristic of oak tannins, whereas gall plant tannins could be differentiated by their content of pinitol. Myo-inositol and arabitol were detected in tannins from quebracho. These polyalcohols, together with muco-inositol and chiro-inositol, were found in tannins from chestnut while bornesitol was found to be characteristic of tannins from gambier. Monosaccharide composition also helped to distinguish among tannin origins: arabinose, xylose, fructose and glucose were quantified in oak, quebracho and chestnut tannins, whereas only fructose and glucose were detected in plant gall and grape tannins. These results imply that the qualitative study of monosaccharides and polyalcohols could help to determine and control the authenticity of enological tannins. 相似文献
73.
74.
José M. Sendra José V. Carbonell Maria J. Gosalbes Victoria Todo 《Journal of the Institute of Brewing》1989,95(5):327-332
The FIA-fluorimetric methods for the determination of β-glucan in worts and beers have been investigated, modified and improved. Fluorescence is excited by using a mercury lamp and a 338 nm band-pass excitation filter, and detected using a 425 nm long-pass emission filter. It has been found that an increase of the ionic strength of the eluent, up to a maxium of 1% Sodium Chloride, increases the range of β-glucan molecular weights effectively bound by Calcofluor. The influence of the low molecular weight components of wort and beer: dextrins, aminoacids, etc, has been studied and found that their effect is negligible. The interference of wort and beer colour on the measurement of β-glucan has been quantified and several approaches are given to overcome it. Thirty-six European beers have been analyzed for β-glucan content. The possible detection of the addition of exogenous β-glucanases to wort and beer is discussed. 相似文献
75.
Galinsky Adam D.; Mussweiler Thomas; Medvec Victoria Husted 《Canadian Metallurgical Quarterly》2002,83(5):1131
Three experiments explored the role of negotiator focus in disconnecting negotiated outcomes and evaluations. Negotiators who focused on their target prices, the ideal outcome they could obtain, achieved objectively superior outcomes compared with negotiators who focused on their lower bound (e.g., reservation price). Those negotiators who focused on their targets, however, were less satisfied with their objectively superior outcomes. In the final experiment, when negotiators were reminded of their lower bound after the negotiation, the satisfaction of those negotiators who had focused on their target prices was increased, with outcomes and evaluations becoming connected rather than disconnected. The possible negative effects of setting high goals and the temporal dimensions of the disconnection and reconnection between outcomes and evaluations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Hiromichi Fujii Victoria A. Yardley Takashi Matsuzaki Sadahiro Tsurekawa 《Journal of Materials Science》2008,43(11):3837-3847
The effect of a magnetic field on the nature of nanocrystallization from a melt-spun Fe73.5Si13.5B9Nb3Cu1 amorphous precursor has been studied with the aim of controlling microstructures and magnetic properties. Annealing for magnetic
crystallization was carried out at temperatures between the Curie temperature of the amorphous phase (586 K) and that of the
crystalline phase (920 K). It was found that the {110} texture component in crystallized α-Fe(Si) phase increased in importance
with increasing magnetic-field strength. An X-ray diffraction analysis based on the Shultz method revealed that the magnetic
field caused preferential formation of {110}-oriented nuclei. In addition, the applied field enhanced crystallization kinetics,
particularly the nucleation rate. No significant difference in grain growth behavior was observed as a result of applying
a magnetic field. We therefore conclude that the development of the {110} texture by magnetic crystallization is predominantly
attributable to preferential nucleation, rather than preferential growth, of {110}-oriented nuclei. The saturation magnetization
of nanocrystallized specimens, evaluated using a vibrating sample magnetometer (VSM), was increased by the application of
a magnetic field up to 4T during nanocrystallization. 相似文献
77.
78.
josé A. Iba?ez L. Victoria Rafael M. Barzanallana 《Journal of Automated Methods and Management in Chemistry》1989,11(3):129-133
An integrated computer system consisting of an expandable
ionanalyzer and a PC has been used to automate concentration
measurements with ion-selective electrodes (ISEs). The ionanalyzer
determines ionic concentrations using a reference electrode
coupled with an ISE. The measurements and calibrations are
carried out in a thermostated sample changer equipped with a flow
cell. The data obtained by the ionanalyzer are sent via a standard
RS 232-C interface to a microcomputer. In this paper, we describe
the automatic data acquisition system and the subsequent processing
of the measurements. One program (Transorion) automatically
collects the measurements carried out by the ionanalyzer, giving a
real-time graphic representation of the measurement on the
computer screen. A second program (Graforion) facilitates the
management of the data stored by the first program, and listing and
graphics of these can be obtained on the printer/plotter. The method
has been used to study continuous concentration changes in an
aqueous solution of potassium iodide. 相似文献
79.
High-Fat Diet Alters Serum Fatty Acid Profiles in Obesity Prone Rats: Implications for In Vitro Studies 下载免费PDF全文
Liu Tzu-Wen Heden Timothy D. Matthew Morris E. Fritsche Kevin L. Vieira-Potter Victoria J. Thyfault John P. 《Lipids》2015,50(10):997-1008
High‐fat diets (HFD) are commonly used in rodents to induce obesity, increase serum fatty acids and induce lipotoxicity in various organs. Invitro studies commonly utilize individual free fatty acids (FFA) to study lipid exposure in an effort to model what is occurring in vivo; however, these approaches are not physiological as tissues are exposed to multiple fatty acids in vivo. Here we characterize circulating lipids in obesity‐prone rats fed an HFD in both fasted and fed states with the goal of developing physiologically relevant fatty acid mixtures for subsequent in vitro studies. Rats were fed an HFD (60 % kcal fat) or a control diet (10 % kcal fat) for 3 weeks; liver tissue and both portal and systemic blood were collected. Fatty acid profiles and absolute concentrations of triglycerides (TAG) and FFA in the serum and TAG, diacylglycerol (DAG) and phospholipids in the liver were measured. Surprisingly, both systemic and portal serum TAG were ~40 % lower in HFD‐fed compared to controls. Overall, compared to the control diet, HFD feeding consistently induced an increase in the proportion of circulating polyunsaturated fatty acids (PUFA) with a concomitant decline in monounsaturated fatty acids (MUFA) and saturated fatty acids (SFA) in both serum TAG and FFA. The elevations of PUFA were mostly attributed to increases in n‐6 PUFA, linoleic acid and arachidonic acid. In conclusion, fatty acid mixtures enriched with linoleic and arachidonic acid in addition to SFA and MUFA should be utilized for in vitro studies attempting to model lipid exposures that occur during in vivo HFD conditions. 相似文献
80.
Victoria Derr 《CoDesign》2015,11(2):119-133
This article shares outcomes from a year-long participatory planning process – one that brought together children and youth engagement, city planning, campus planning, and a university environmental design course to explore child-friendly, dense and affordable housing for a city of approximately 100,000 residents. This process of engagement asked design students to include youth participation and child-friendly cities as an integrated component of sustainable cities. The article shows varying degrees of transformation, views of children as credible participants, and values gained from the project. Many undergraduates changed their thinking about the role of young people in design processes and outcomes. 相似文献